Such a study should be placed within the larger research context of crosscultural musical interaction in general. There seems to be no limit to the ways in which cultures react to external musical elements. Sometimes only musical instruments are borrowed, without any absorption of the original music; other times, conversely, only a melody is taken and played on the instruments of the borrowing culture. Sometimes it is only a rhythm, sometimes only a polyphonic technique, sometimes a tuning system that is adopted. The reasons for borrowing are also diverse, often involving motives other than aesthetic ones; thus the Japanese adopted Western music as the standard in their schools in the 1870s, not because they preferred it, but because they believed this would help them catch up with the West economically and politically. The mechanisms of borrowing are also varied and can operate in either wartime or peacetime. In earlier centuries in mainland Southeast Asia, for example, the court musicians of a defeated kingdom would often be absorbed into the court of the conquering power (cf. Morton 1976: ch. 1); since the balance of power shifted frequently, the classical musical systems of what are now Thailand, Laos, Cambodia and Burma came to share most of their basic features.